overview

Fujinon’s MK 50-135 T2.9 is a lightweight, compact, E-mount zoom lens.
The MK 50-135 T2.9 is the second in a new series of Fujinon E-mount zooms. 
 It features a mechanical design with three independent lens control rings: focus, iris, and zoom. Each ring incorporates a cine-style gear with a 0.8 MOD for interfacing with standard cine -style lens accessories. The focus ring features approximately 200° of rotation, which provides room or precise focus pulls, and the iris is clickless, enabling smooth iris pulls. The lens also incorporates a macro mode for close focusing capabilities.
The lens is color matched to other Fujinon lenses such as the HK, ZK, and XK series, which enables smooth intercutting between lenses. The 85mm front enables use with many cine-style matte boxes via use of optional step up rings (rings not included). The lens weighs just under 1 kg, which is fairly light for a cinema zoom that holds focus and aperture throughout the focal length range. It is designed for camera's with a Sony E-mount, so it has a short flange focal distance, but the lens allows for flange focal distance adjustment so you can fine tune it to the camera you are using the lens on.

• T2.9 to T22 aperture with 9 iris blades for attractive bokeh
• The 28.5mm diameter image circle covers the 3-perf super 35 format with a 16:9 aspect ratio
• Industry standard 0.8 film pitch gears for focus, zoom, and iris control
• The gear rings positions for focus, zoom, and iris are located at the same position on both lenses in the MK series, making switching between the two zooms quick as you don't have to adjust the position of lens accessories
• Both lenses in the MK series have the same weight and length so here is no need to rebalance your camera when you change from one lens to the other
• 200° focus barrel rotation
• No shims are required to adjust the flange focal distance as this lens has a built-in adjustment mechanism
• Macro focus function available

More info here.